Beckhoff FC3101, Documentation

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FC310x as master
FC3101 and FC3102 43 Version: 3.0
PROFIBUS Mode : This is where the selection is made between master [ } 10] functionality (the default
setting) and slave [ } 64] functionality.
Auto-Clear-Mode : It is possible to specify here whether the master enters (or stays in) the "Clear" state as
long as either at least one MC slave (the "Only MC-Slaves" setting) or any slave (the "All Slaves" setting)
does not respond correctly (has a
DpState [ } 25] other than 0) (see the Error Reactions [ } 16] chapter).
Clear-Delay : The DP master changes automatically into the clear mode (the outputs of the slaves are set
either to 0 or to the fail-safe values) when it ceases to receive an interrupt from the associated task (e.g. a
PLC breakpoint has been reached, or the system has crashed). It is possible to specify here how many
missing tasks cycles can be tolerated before the master switches into the clear mode. This setting is
independent of the setting in the
Auto-Clear-Mode .
Operate-Delay : The DP master changes automatically, observing the Auto-Clear-Mode, into the operate
state when the task is started. The transition from Clear to Operate can be delayed with the Operate delay
time. In the Clear state, all the outputs are set to 0 (if the DP slave does not support Fail_Safe values) or to
the Fail_Safe value (if the DP slave supports Fail_Safe), whereas in the Operate state the outputs have the
values specified by the task.
Reaction on PLC-STOP : It is possible to specify here whether the DP master should set the outputs to 0
when reaching a PLC stop or breakpoint, or should leave them unchanged (see the Fault Reactions [ } 16]
chapter).
Redundancy-Mode : Redundancy mode can be set here for the DP master. In that case all that it does is to
listen to the bus (see the Master Redundancy [
}
38] chapter).
SetPrm-Unlock before DP-Start-Up : Normally, during DP start-up, the DP master removes the cyclic
connections, so that the DP slave can always recognize that the DP master has restarted. In redundancy
mode, however, it may be specifically desirable for the DP slave to remain unaware of this, because the
switch-over from the primary master to the redundant master should not have any interactions for the DP
slave (see the
Master Redundancy [ } 38] chapter).
SetPrm-Unlock at DP-Shutdown : Normally, during DP shut-down, the DP master removes the cyclic
connections, so that the DP slave can always recognize that the DP master has stopped. In redundancy
mode, however, it may be specifically desirable for the DP slave to remain unaware of this, because the
switch-over from the primary master to the redundant master should not have any interactions for the DP
slave (see the
Master Redundancy [
}
38] chapter).